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Hazardous Location Emergency Lights & Exit Signs – Complete Guide

Hazardous Location Emergency Lights & Exit Signs – Complete Guide

Overview

Hazardous location emergency lights and exit signs are vital for keeping workers safe in environments where explosive gases, vapors, or combustible dust may be present. These locations include oil refineries, chemical processing plants, paint spray booths, grain silos, and textile mills—places where a single spark could cause disaster.

Unlike standard emergency lights, these fixtures are specifically designed to prevent ignition. Housings are explosion-proof, lamps are enclosed, and internal circuitry is shielded from the surrounding atmosphere. They also comply with rigorous safety standards like UL 844 and NEC Class/Division ratings to ensure suitability for harsh, dangerous conditions.

In this guide, you’ll learn how to identify the correct fixture based on Class and Division, ensure compliance with OSHA and NFPA 101, and choose between exit signs, emergency lights, and combo units. We’ll cover critical buying factors like lettering color, single vs. double face options, self-testing diagnostics, battery backup runtime, and materials used in construction.

💡 Highlight: Every hazardous location light or exit sign must be matched to its specific Class and Division rating—using the wrong fixture in a volatile environment is a serious safety violation. To ensure full compliance and safety, shop explosion proof exit signs or browse explosion proof emergency lights built for industrial and classified spaces.

Hazardous Location Classification: Classes & Divisions

Class 1 Division 1 Edge-Lit Exit Sign

The National Electrical Code (NEC) defines hazardous locations based on the presence of flammable substances and how often those substances are present. Understanding these classifications is essential when selecting lighting and signage for dangerous environments.

Classes describe the type of hazardous material present:

  • Class I: Flammable gases or vapors (e.g., gasoline, hydrogen)
  • Class II: Combustible dusts (e.g., grain dust, coal dust)
  • Class III: Ignitable fibers or flyings (e.g., cotton, wood shavings)

Divisions indicate how often the hazard is present in the environment:

  • Division 1: Hazard is present under normal operating conditions
  • Division 2: Hazard is present only under abnormal conditions (e.g., leaks, system failures)
💡 Pro Tip: Always verify the hazard classification of your environment before selecting emergency lighting—choosing a lower-rated fixture can result in code violations and serious safety risks. For approved fixtures in gas or vapor-prone environments, explore Class I Division 2 emergency lights designed specifically for these hazardous applications.

Compliance and Safety Requirements

Hazardous location emergency fixtures must meet strict national safety regulations and certifications to be legally installed and operated in high-risk environments. These standards ensure that the units provide reliable illumination during emergencies and do not pose additional ignition risks themselves.

  • UL 844 & UL 924 Listings: UL 844 certifies lighting fixtures for hazardous locations, while UL 924 governs emergency lighting and power systems. Your selected unit must carry both listings to satisfy building and fire codes.
  • NFPA 101 (Life Safety Code): Requires emergency egress lighting to illuminate escape paths for a minimum of 90 minutes during power failure. This applies equally to hazardous and non-hazardous areas.
  • OSHA Requirements: OSHA references NFPA and NEC guidelines and enforces compliance. Employers are responsible for ensuring that fixtures are installed and maintained according to these standards.
  • NEC Article 500-506: These articles define how hazardous locations are classified and how electrical equipment must be rated and installed in those locations.
Reminder: Even if a fixture is explosion-proof, it must also meet emergency lighting and exit sign codes such as UL 924 and NFPA 101 to be compliant.

Combo Units vs. Separate Units

In hazardous locations, both types must still meet the same UL 924 and UL 844 requirements. Always confirm that each unit is properly rated for the class/division of your environment.

If you're looking for a space-saving, code-compliant solution, consider a combo exit sign with lights. These integrated units combine clear exit marking with reliable emergency illumination—ideal for minimizing wall clutter and simplifying installation.

Reminder: In hazardous locations, both exit sign/emergency light combo units and separate fixtures must meet UL 924 and UL 844 standards. Always ensure the unit is rated for the correct Class and Division.

Summary

Choosing the correct emergency lighting and exit signage for hazardous locations involves balancing safety, compliance, and performance. Start by identifying the environment’s Class and Division rating to ensure explosion-proof compatibility. Confirm each fixture meets all relevant codes, including UL 844, UL 924, NFPA 101, and OSHA regulations.

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